Photographic film with laminated support having increased flexibility



PHOTOGRAPHIC FILM WITH LAMINATED SUPPORT HAVING INCREASED FLEXIBILITY Filed Dec. 26, 1922 EmZQgfa/UZZZ'CQZ@ Sezzszve layer.

INVENTOR tlwnaslhsg ATTORNEY Patented dan. 6,1925. y

irse? stair 11;

JAMESH. HAsTE, OE ROCHESTER, NEW YO PANY, OE ROCHESTER, NEWYOR RK, ASSIGNOR TO EASTMAN KODAK OOM- K, A oORi-'oRiiTIoui OE NEW YORK.-

Application filed December 26, 1922. Serial No. 609,124.

To all whom t iuzg/ concern.' l

Be it known that I, JAMES H. HASTE, a citizen of the United States of America, residing at Rochester, and State of New York, have-invented certain new and useful Improvements in Photographic Films with Laminated Supports Havin which the followin exact specification.

This -invention relates to photo/graphic ilm, the base of which is laminated. The 4principal object lof the invention is to so construct the film that the flexibility thereof will be' increased both as regards degree and permanence. Other objects will hereinafter appear. In the accompanying drawing the single figure shows in diagrammatic crosssection g isa full, clear, and

uphn an exaggerated scale a film embodying one form of my invention. l While endeavoring to increase the `flexiin the county of Monroe` g Increased '.Flexibility, of

bility of photographic films both as regards:

'the degree of flexibility and the time during which the flexibility Will last,u I have discovered that the desired result may be Aobtained by providing a laminated support. the layers of which arejnterunited ythroughout their entire adjacent faces, the-material present in the zoneI or layer of 'interunion containing a' greater amount of flexibilityinducing material than the main bodies of the supporting layers or la'minations. For p these laminations I prefer to' use compositionsbconsisting chiefly` of cellulose addition ,"compounds, such as cellulose nitrate, cellulose acetate and cellulose ether. The layersA of these substances may contain the usual flexibility-inducing substances, such'as butyl or amyl alcohol, butyl or amyl acetate, monochlornaphthalene, tricre v castor oil, ethyl -propionate, ethyl butyrate.

' This list is intended merely to be illustrative.

The flexibility-inducing substances cannot present in too large an. amount in the syl phosphate,

laminations without impairing other qualities of the film, such as strength, hardness'` and the like. The fact has been established,

ing the 1am-mations containing considerable amounts of flexibility-in ucing material, the flexibility of the be Surprisingly hOWeverLthat if a cement be used for unit-V increased abovey what might be expected when the relative' thinness of the' interunit- 55 ingzone is considered. The flexibility-inducingmaterial in thecement is added to and blended with the composition in the zone which already contains the normal amount of flexibility-inducing material. Consequently a reservel or high percentage of the latter is built upI in said zone. In other Words, at the zone .there is an intermingling of the compositions composing the laminations with the oementing material. The .volatile ingredients of -the cement rapidly Work outward through the bodies of the layers, but the'relatively high-boiling flexibility-inducing substances remain in the form of a reserve in the zone of interunion..where they continue to function considerably longer than the normal amounts of flexibility-inducing substancesk do in conventional films of ordinary composition and structure.

\ Referring to the drawing in whiolrone embodiment of my invention is shown., by way of illustration, l indicates the photographically sensitive layer Jof any usual or preferred form,--say a layer of gelatino silver 'haloid emulsion. The supportingl layers' of cellulosic addition compounds are indicated at 2. ,In the preferred form of myrinvention these layers are composed of nitro-cellulose and flexibility-inducing sub- 85l stances such as butyl alcohol and small I amounts of castor oil or camphor. .These llayers are preferably formed as separate sheets and then cemented together in any known or preferred proce or apparatus for laminating suchsheets by `means of a 'cement containing a yreserve of flexibility-v inducingmaterial. One suitable cement, by way ofillustration, is acetone 20 parts, methyl alcohol 20 parts, methyl acetate 40 V95 parts, butyl acetate 19- partsfnitrocellulose a trace,'say 1 part, and a flexibility-inducing material such as monochlornaphthalene, tricresyl phosphate orbutyfl alcohol,` stor Oil, etc., from 2 to 10 parts. No matter what the percentage of Hexibility-inducing material be in the compositions of the laminations, lth'e zone of interunion formed by the blending action vof the cement will oontain in addition the` fl material introduced by the exibility-indueng v 'faces, lthan said layers and containing .compound from said layers and also com taining a greater proportionv of iexibilitygraphic lm comprising a photograp icallyv sensitive layer and a laminated,` eXible, transparent, support-. therefor, vsaid support includin a plurality of layers ofl cellul'os'ic ad ition compound, mixed With flexibility-inducing 'materiaL said layers being4 interun'ited thro/ughout their entire adjacent this zone ofzinterunion beingl thinner cellulosic inducing material than. said layers, thereby embodying a reserve-'of said material. l

2. As an article of manufacture, a photographic/,61m comprising a photographically sensitive ,layerg and laminated, flexible, trans-4 parent, support therefor, said support including tWo layers of nitrocellulose composition united throughout their entire adjacent faces, this zone of interunionbein thinner than said layers and containing nitrocellulose from said layersanch also containing a reserve of lexibilityeinducing material of 10W` volatility.

Signed at Rochester, New York, this 16th day of December, 1922.

JAMES ii. vrnisriej 

